Unable to get sendmail submission port to listen on IPv6

[Beat Siegenthaler]

Hi all,

I did not recognize that 587 is only listening onIy on IPv4. Maybe it's
new, maybe it was alltime so.

sendmail  25090        root    4u  IPv4 0xfffffe01e810f3d0      0t0   
TCP *:25 (LISTEN)
sendmail  25090        root    5u  IPv6 0xfffffe01a988f000      0t0   
TCP *:25 (LISTEN)
sendmail  25090        root    6u  IPv4 0xfffffe011c53d000      0t0   
TCP *:587 (LISTEN)

FreeBSD 9.1-STABLE #8 r248707

freebsd.submit.mc states:

dnl If you use IPv6 only, change [127.0.0.1] to [IPv6:::1]
FEATURE(`msp', `[127.0.0.1]')dnl

But IPv6:::1 makes no difference, same picture only listen v4.

hostname.domain.com grown over the years. TLS, some milters, SRS Hack.
And working fine so far.

Any hint for me?

kind regards,
Beat